BMW X5 4.4 with 200.000 km

[petroscf]

Would you decide to buy a used (2 previous owners afa I understood) X5 model '06 (E53 with facelift I think?) with 200.000 km on the odo?
What issues do 4.4 give, as the next owner of this one, is probably going to be dealing with them? (and I guess the prices will be ouch!)
Any experience-knowledge will help.
Oh, plus it is lpg converted

[uwbuurman]

Engine is pretty foolproof, but a x5 with v8 is not very economical to run. LPG on the v8 is not common, but Loentje just bought a 540 e39 on LPG, I believe it has done 250k km.

[petroscf]

Heard a couple of things about transmissions not bullet proof, especially on V8, because of high vibration (?)
If this is the case, I am afraid that at 200000, a dead transmission could easily be the next issue (or a near future one)

Other issues I was told (or thinking about myself) are:

1) suspension? I guess this would be the time to replace, so this lot would probably fall to me!, and yes, I guess the suspension on this car will be very expensive..
2) Some one told me he wouldn't buy a bmw with lpg conversion where he wouldn't know who did the conversion, as you have someone not bmw technician, drilling your inlet..